Okay, here's something I see and think.
the smith's daughter the POV character with the opening taking place within the hillfort detailing the siege and the run up to it in order to give the reader a better connection to the characters' motivations. She will still meet the other protagonist in the wooded valley after he jumps from the ship and the plot will continue from there.
I think you should do the old setting, it had potential. Also, the newer plot doesn't have a hook to get my attention like the other plot.
The story will start with Caoímhe helping to load the boat in which the other protagonist is departing with trading supplies including a talisman resembling a tall, bearded man. This will have been received from the fortress to the north of them in exchange for weaponry. After seeing them off on their journey to the lands to the west, she returns to work with her father. A few days after the crew's departure, an army will arrive at their gates and begin a siege, but in the dead of night, the siege turns into a storm as burning embers are shoved between the palisades and the defenders are soon forced back. Within hours, the settlement will have fallen, with Caoímhe forced into hiding beneath their house by her father.
Now, personally I would use this in the new plot but it's ultimately up to the writer. I am free around anywhere between 10 am - 5 pm if you want any advice or on Friday- Monday.
After a night of watching, it becomes clear that Aengus' army made short work of the little raiding party, leaving Caoímhe and Fergus with few options except to walk to their neighbours to the north and beg them for help, which they both do reluctantly. It takes them a full day of walking and they practically crumple into a heap when they arrive at the town to their north. The following day they're given an audience with the town's elders who are sympathetic to their plight but are apprehensive about lending military aid to the village. That night their hand is forced when they wake up to find Aengus at their gates with his army.
Now, I see a bloody mess of the way you described the situation of the characters.
